A process kit shield may be used in, for example, a physical vapor deposition (PVD) chamber to separate a processing volume from a non-processing volume. In PVD chambers configured to deposit aluminum on a substrate, the process kit shield may be fabricated, for example, from stainless steel (SST). The SST process kit shield can be recycled multiple times as an aluminum layer deposited on the process kit shield during processing can be etched away from the base SST shield material. However, the inventors have been working on depositing relatively thick aluminum films on the substrate using significantly increased process power and deposition time as compared to conventional aluminum deposition processes.
For high deposition processes, deposition accumulation on the process kit builds up significantly to the point where the deposition can build up to the back of the substrate. At that point, the deposition can adhere or stick to the back of the substrate, which can cause substrate handling issues and lead to broken substrates.
Accordingly, the inventors have provided embodiments of improved process kits as disclosed herein.